Interpretive Summary: Working with the North American invasive weed in the Mediterranean region, silverleaf nightshade, a new technique was developed for extraction of DNA. The new method yields good quality DNA that can be used for, among other things, amplification and detection of microsatellites.

Technical Abstract:
The geographical origin of an invasive in the cultivated area within the Mediterranean region, silverleaf nightshade, Solanum elaeagnifolium Cav, (Solanaceae) should be identified through the analysis of genetic similarities between native and introduced populations using microsatellite markers. Beforehand, an effective and less costly method for extracting genomic DNA from dehydrated and polysaccharide–rich leaves was investigated. The original Doyle’s protocol based on the use of a cationic detergent, CTAB, was successfully optimized in order to extract high quality DNA (A260/280 ratio of 1.8; A260/230 ratio of 1.7 to 2). The DNA yields obtained with this new protocol were higher than those obtained with the commercial kit, although quality of the DNA extracted was comparable. The improvement of the protocol was further proven by the amplification of several microsatellite loci developed in eggplant, S. melongena L.